OP0277 PERSISTENT EXCESS OF STROKE EVENTS IN RHEUMATOID ARTHRITIS: A RETROSPECTIVE COHORT STUDY FROM HORDALAND, NORWAY FROM 1972 TO 2014
Authors: C. L. Alsing, J. Igland, G. S. Tell, H. Næss, T. W. Nystad, B. T. Svanes Fevang
Journal: Annals of the Rheumatic Diseases (2022)

Background Patients with rheumatoid arthritis (RA) have an excess risk of cardiovascular disease (CVD), including stroke [1]. After the introduction of biological DMARDs in 1999 and the treat to target strategy, more patients reach low disease activity and remission, which is associated with lower CVD risk [2]. Few previous studies have examined stroke occurrence in RA patients before and after these improvements in RA management. Objectives To investigate stroke events in RA patients diagnosed before and after 1999 compared with the total population. Methods We included 771 RA patients diagnosed during 1972-1998 and 1050 during 1999-2013 at the main rheumatological department of Hordaland county, Norway. The total population of the same county and time period were used as a comparison cohort. Data on stroke events were obtained from regional cardiovascular registries or hospital patient administrative systems during 1972-2014. Aggregated counts of stroke events and population counts from the comparison cohort were used to estimate expected counts of stroke hospitalisation in the RA cohort per 5-year age group, sex and calendar year. We then estimated standardised event ratios (SERs) by Poisson regression as a measure of excess stroke events in RA patients compared with the total population. Results In total, 152 stroke events occurred in 112 RA patients diagnosed during 1972-1998 over 15137 person-years of follow-up and 86 stroke events in 70 RA patients diagnosed during 1999-2013 over 8672 person-years of follow-up. RA patients diagnosed in the later period were on average 2.1 years older (56 years) at RA diagnosis, but the proportion of women was similar in both groups. Both RA patients diagnosed before and after 1998 had an excess of stroke events compared with the total population (SER 1.20, 95% CI 1.00-1.44 and SER 1.22, 95% CI 1.05-1.42 respectively). RA patients younger than 60 years of age did not appear to have significant excess stroke events in either group. Conclusion These results indicate a similar excess of stroke events in RA patients diagnosed before and after 1999. This warrants continued awareness regarding stroke prevention in RA patients, even after the recent improvements in RA treatment. References [1]Wiseman SJ, Ralston SH, Wardlaw JM. Cerebrovascular Disease in Rheumatic Diseases: A Systematic Review and Meta-Analysis. Stroke 2016;47:943–50. [2]Myasoedova E, Chandran A, Ilhan B, et al. The role of rheumatoid arthritis (RA) flare and cumulative burden of RA severity in the risk of cardiovascular disease. Ann Rheum Dis 2016;75:560–5. Figure 1. Standardised event ratios (SER) comparing stroke events in RA patients with the total population of Hordaland, Norway, given with 95% robust confidence intervals. Seperate estimates were calculated for the entire RA cohort and 6 RA subcohorts defined by age, sex, positive rheumatoid factor or ACPA and arthritis on x-ray during follow-up. ACPA, anti-citrullinated protein antibodies; ACR, American College of Rheumatology; EULAR, European League against Rheumatism; RA, rheumatoid arthritis; RF, rheumatoid factor. Acknowledgements This work was funded by the Western Norway Regional Health Authority, Marit Hansen’s Memorial fund and Aslaug Andersen’s Memorial fund. Disclosure of Interests Christian Lillebø Alsing: None declared, Jannicke Igland: None declared, Grethe S. Tell: None declared, Halvor Næss Speakers bureau: Pfizer, BMS, Tone Wikene Nystad: None declared, Bjørg Tilde Svanes Fevang Speakers bureau: Part of discussion board at UCB conference on spondyloarthritis, Consultant of: Part of advisory board Lilly